Square Roots

🏆Practice root of a root

Square Roots

When we encounter an exercise in which there is a root applied to another root, we will multiply the order of the first root by the order of the second and the order obtained (the product of both) will be raised as a root in our number (as generally power of a power)
Let's put it this way:  

root of root unknowns

Start practice

Test yourself on root of a root!

einstein

Solve the following exercise:

\( \sqrt{\sqrt{2}}= \)

Practice more now

Let's look at this in the example

root of root numbers

6423=646=2 \sqrt[3]{\sqrt[2]{64}}=\sqrt[6]{64}=2


If you are interested in this article, you may also be interested in the following articles:

Laws of Radicals

The Root of a Product

Root of the Quotient

Combining Powers and Roots

In the blog of Tutorela you will find a variety of articles about mathematics.


Examples and exercises with solutions on root extraction

Exercise #1

Solve the following exercise:

2= \sqrt{\sqrt{2}}=

Video Solution

Step-by-Step Solution

To solve 2\sqrt{\sqrt{2}}, we will use the property of roots.

  • Step 1: Recognize that 2\sqrt{\sqrt{2}} involves two square roots.
  • Step 2: Each square root can be expressed using exponents: 2=21/2\sqrt{2} = 2^{1/2}.
  • Step 3: Therefore, 2=(21/2)1/2\sqrt{\sqrt{2}} = (2^{1/2})^{1/2}.
  • Step 4: Apply the formula for the root of a root: (xa)b=xab(x^{a})^{b} = x^{ab}.
  • Step 5: For (21/2)1/2(2^{1/2})^{1/2}, this means we compute the product of the exponents: (1/2)×(1/2)=1/4(1/2) \times (1/2) = 1/4.
  • Step 6: The expression simplifies to 21/42^{1/4}, which is written as 24\sqrt[4]{2}.

Therefore, 2=24\sqrt{\sqrt{2}} = \sqrt[4]{2}.

This corresponds to choice 2: 24 \sqrt[4]{2} .

The solution to the problem is 24 \sqrt[4]{2} .

Answer

24 \sqrt[4]{2}

Exercise #2

Solve the following exercise:

535= \sqrt[5]{\sqrt[3]{5}}=

Video Solution

Step-by-Step Solution

To solve the problem of finding 535 \sqrt[5]{\sqrt[3]{5}} , we'll use the formula for a root of a root, which combines the exponents:

  • Step 1: Express each root as an exponent.
    We start with the innermost root: 53=51/3 \sqrt[3]{5} = 5^{1/3} .
  • Step 2: Apply the outer root.
    The square root to the fifth power is expressed as: 51/35=(51/3)1/5 \sqrt[5]{5^{1/3}} = (5^{1/3})^{1/5} .
  • Step 3: Combine the exponents.
    Using the exponent rule (am)n=am×n(a^m)^n = a^{m \times n}, we get:
    (51/3)1/5=5(1/3)×(1/5)=51/15(5^{1/3})^{1/5} = 5^{(1/3) \times (1/5)} = 5^{1/15}.
  • Step 4: Convert the exponent back to root form.
    This can be written as 515 \sqrt[15]{5} .

Therefore, the simplified expression of 535 \sqrt[5]{\sqrt[3]{5}} is 515 \sqrt[15]{5} .

Answer

515 \sqrt[15]{5}

Exercise #3

Solve the following exercise:

11010= \sqrt[10]{\sqrt[10]{1}}=

Video Solution

Step-by-Step Solution

To solve this problem, we'll observe the following process:

  • Step 1: Recognize the expression 11010 \sqrt[10]{\sqrt[10]{1}} involves nested roots.
  • Step 2: Apply the formula for nested roots: xmn=xnm \sqrt[n]{\sqrt[m]{x}} = \sqrt[n \cdot m]{x} .
  • Step 3: Set n=10 n = 10 and m=10 m = 10 , resulting in 110×10=1100 \sqrt[10 \times 10]{1} = \sqrt[100]{1} .
  • Step 4: Simplify 1100 \sqrt[100]{1} . Any root of 1 is 1, as 1k=1 1^k = 1 for any positive rational number k k .

Thus, the evaluation of the original expression 11010 \sqrt[10]{\sqrt[10]{1}} equals 1.

Comparing this result to the provided choices:

  • Choice 1 is 1 1 .
  • Choice 2 is 1100 \sqrt[100]{1} , which is also 1.
  • Choice 3 is 1=1 \sqrt{1} = 1 .
  • Choice 4 states all answers are correct.

Therefore, choice 4 is correct: All answers are equivalent to the solution, being 1.

Thus, the correct selection is: All answers are correct.

Answer

All answers are correct.

Exercise #4

Solve the following exercise:

26= \sqrt[6]{\sqrt{2}}=

Video Solution

Step-by-Step Solution

Express the definition of root as a power:

an=a1n \sqrt[n]{a}=a^{\frac{1}{n}}

Remember that in a square root (also called "root to the power of 2") we don't write the root's power as shown below:

n=2 n=2

Meaning:

a=a2=a12 \sqrt{a}=\sqrt[2]{a}=a^{\frac{1}{2}}

Now convert the roots in the problem using the root definition provided above. :

26=2126=(212)16 \sqrt[6]{\sqrt{2}}=\sqrt[6]{2^{\frac{1}{2}}}=\big(2^{\frac{1}{2}}\big)^{\frac{1}{6}}

In the first stage we applied the root definition as a power mentioned earlier to the inner expression (meaning inside the larger-outer root) and then we used parentheses and applied the same definition to the outer root.

Let's recall the power law for power of a power:

(am)n=amn (a^m)^n=a^{m\cdot n}

Apply this law to the expression that we obtained in the last stage:

(212)16=21216=21126=2112 \big(2^{\frac{1}{2}}\big)^{\frac{1}{6}}=2^{\frac{1}{2}\cdot\frac{1}{6}}=2^{\frac{1\cdot1}{2\cdot6}}=2^{\frac{1}{12}}

In the first stage we applied the power law mentioned above and then proceeded first to simplify the resulting expression and then to perform the multiplication of fractions in the power exponent.

Let's summarize the various steps of the solution thus far:

26=(212)16=2112 \sqrt[6]{\sqrt{2}}=\big(2^{\frac{1}{2}}\big)^{\frac{1}{6}} =2^{\frac{1}{12}}

In the next stage we'll apply once again the root definition as a power, (that was mentioned at the beginning of the solution) however this time in the opposite direction:

a1n=an a^{\frac{1}{n}} = \sqrt[n]{a}

Let's apply this law in order to present the expression we obtained in the last stage in root form:

2112=212 2^{\frac{1}{12}} =\sqrt[12]{2}

We obtain the following result: :

26=2112=212 \sqrt[6]{\sqrt{2}}=2^{\frac{1}{12}} =\sqrt[12]{2}

Therefore the correct answer is answer A.

Answer

212 \sqrt[12]{2}

Exercise #5

Solve the following exercise:

8= \sqrt[]{\sqrt{8}}=

Video Solution

Step-by-Step Solution

In order to solve the given problem, we'll follow these steps:

  • Step 1: Convert the inner square root to an exponent: 8=81/2\sqrt{8} = 8^{1/2}.

  • Step 2: Apply the root of a root property: 8=(8)1/2=(81/2)1/2\sqrt{\sqrt{8}} = (\sqrt{8})^{1/2} = (8^{1/2})^{1/2}.

  • Step 3: Simplify the expression using exponent rules: (81/2)1/2=8(1/2)(1/2)=81/4(8^{1/2})^{1/2} = 8^{(1/2) \cdot (1/2)} = 8^{1/4}.

The nested root expression simplifies to 81/48^{1/4}.

Therefore, the simplified expression of 8\sqrt{\sqrt{8}} is 814 8^{\frac{1}{4}} .

After comparing this result with the multiple choice answers, choice 2 is correct.

Answer

814 8^{\frac{1}{4}}

Join Over 30,000 Students Excelling in Math!
Endless Practice, Expert Guidance - Elevate Your Math Skills Today
Test your knowledge
Start practice